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Closed bolt.

Vegeta writes:
"To me, Bud Orr isn't innovative.. *poof* !"

Just to set the record straight:
Bud didn't put a ram on his guns until I showed him how to adapt my system to his guns. However, you are close to the reason why pumps got automated. I built the first functional, gravity fed semi for myself in the fall of 1988 because I have a very bad shoulder left over from a Hi-school football injury and the act of pumping a paintgun several hundred times a day was killing me. I was faced with a choice of either figuring out how to automate my gun or basically quit playing Paintball. I was too badly hooked on the game to quit.

I didn't really mean to dis Bud... but now that I know if was really your idea... hmmm.. I mean your first few pump to semi conversions looked awesome, in my opinon. It's more of a nostalgig feeling of playing with a gun like that than it is on how good the gun performs. I would take one in a heartbeat if I had the chance, as any sane person would. They are pieces of history.. And hopefully in a hundred years when paintball is all changed, ppl will still refer to you, along with bud, Tom, Tippmann... etc for all the accomplishments. Isn't that a great feeling?

That is an awesome story... someone needs to publish it in APG or something. Bud shouldn't get so much credit.. .

During rapid fire, there is absolutely NO difference between open and closed bolt.

Closed bolt:
When firing rapidly, the bolt moves back letting a ball in, then slams forward. Once in the forward position, it will immediately fire the paintball, the move back allowing another paintball to enter the breech. Depending on how fast you can shoot, the paintball should be propelled into the barrel as soon as the bolt even gets in the forward position.

Open bolt:
Just to get this straight with everyone, ALL GUNS THAT ARE UNDER THE SUN FIRE AT THE CLOSED BOLT POSITION. No matter what you say, it's true (with the exception of boltless markers such as the Epic).
Now since that is out of the way, here's how an open bolt marker works under rapid fire. A ball is inserted into the breech of the marker. Upon a trigger pull, the bolt is slammed forward to the forward position, only then is the air released through the bolt onto the paintball. Then the bolt moves backward, allowing another ball in.

Now think about this. Both guns let a paintball inside the breech, slam forward, then release pressurized air (or Co2 in some cases) onto the paintball to be propelled through the barrel. Afterwards, the bolt will move back again, allowing another paintball in, etc. Granted this is only rapid fire, but I do not know anyone that plays paintball by taking 1 shot per every second.

And, just to prove that all guns fire only when the bolt is at it's forward most position (well, forward enough to say that. there may be a .05" difference) I attached a picture of how a Matrix works. Hopefully now you will stop debating which one is better/more accurate/better range and finally figure out that they are exactly the same under rapid fire.

First off, let me say that I'm just a 13 year old and know nothing about science, I just know logic

1.) It is truly the player holding the gun. If you had both guns in a vice grip pointing in the same direction, that is much different. Back when I had my phantom I could hit stuff dead on, because I took the time to line up my shots... where as when I let my friend shoot it, took him 10 shots to hit it :P

2.) The Matrix is neither closed or open bolt... not sure where I read that but it has its own bolt system.

The reason closed bolt seems more accurate is because of the trajectory, the air behind the ball is a small burst of high pressure air. When you fire a cocker, you pull the trigger, the ball is loaded, than the next time you fire the ball is launched before the next ball can even see the breach, the ball is than loaded again, under rapid fire its the same thing, the ball is shot before the next ball is loaded, with open bolt the ball is sitting in a state where it can move around, where as with closed bolt the ball is still for that tiny little bit of a second. When the bolt goes forward , with an open bolt gun, the first ball will have a better trajectory because it is in a still state, but what happens is the bolt slams forward and launches the ball which deforms the ball and shoots it at the same time and because of this deformation air must have to give the ball a slight forward spin, which in turn causes the ball to not shoot as far. If you take a z-bodied mag and get the knob turned right it will shoot just like cockers, because it gets deformed correct? and gets the forward spin, well the zbody reverses that and creates a straight shooting ball, you can even give the ball some backspin and have a automag-flatline. Also, have you thought about when the bolt slams back into place? that has to move the gun around a bit

On the woods recball field, I would take a cocker over an emag... but on an airball field, I would take the emag over a cocker

Why? Cockers have less recoil, which allows them to shoot straighter (I never said more accurate) in rapid fire, since woods fields usually have many hills and things, the straighter the shot the better. But on a speedball/airball course I'd take an emag... why... speed and reliablity. Although i've never had a cocker other than a very old revenge crap out on me. All cockers I've shot required a little bit of timing, which I can do in a few minutes, and they were shooting perfect. With my emag on an airball field, I can shoot plenty of paint, and since the field isn't usually much bigger than 100x30, the range doesn't matter, because I play mid/front, I can pop out and shoot 4-5 shots in half a second... which with my cocker I could shoot maybe 2-3 shots in that half second.

Automags are more consistent 100% I can say that, I had a stock automag with a pure energy 48/3000 and was shooting a perfect 284-285-286, my stock cocker on the other hand with 68/3000 flatline was shooting a good 270-280-290

These are all unscientific ideas, these are my 13 year old thoughts and are all logic... Don't flame me if I sounded stupid...

first of all, a Matrix is open bolt. The way you tell an open bolt from a closed bolt is the position in which the bolt sits at when not being fired. If the breech is open, it's open bolt. If the breech is closed, it's closed bolt. the Matrix does not have it's own bolt system, because there can only be two. You can't have a half and half, and you can't have a left and right. It's either open or closed. The special about the Matrix is the spool valve design. It uses no hammer and no moving parts except the bolt.

Second, I already stated how closed and open bolts perform and act exactly the same when under rapid fire. There's so little time for a closed bolt marker to rest the bolt, then shoot, it just makes no difference. Say I'm rapid firing with a Matrix. And (just for an example) say the bolt is pushed forward, then after 0.03 seconds, air is released. Now say I were rapidly firing a closed bolt marker. The gap between when the bolt is at rest and when it actually fires may be 0.04 or 0.05. The difference is so miniscule, you will so no noticeable difference. Also, the ball you are loading doesn't just stop instantly. It still carries kinetic energy and is moving, just as an open bolt marker would.

I'm pretty sure that Tom Kaye proved that there is no deformation inside the barrel. The paintball moves without any spin, and moves without being deformed when shot through the barrel. Once it leaves the barrel, there are a lot of other variables that take place.

The Z=body is just like a Flatline. It induces back spin on the ball to carry the ball a little further. This is useless and annoying. If you tip the gun, you'll spin the ball slightly right, or slightly left. So, unless you shoot perfectly straigh, your paintball is going to go veering off in the direction of the spin.

Range is entirely dependant on the shape of the ball, the wind, and velocity. Take a marble and set it on a table. Now roll it off. Mark how far it goes. Not take another marble and roll it off too, but with more force. The extra velocity carries it further before it hits the ground. The same thing with paintballs. You shoot a ball at 230 fps, it's not going to go as far as a paintball being shot at 300fps. It's simple logic and proven physics.

As for consistency, that's not really the gun. It's more of the reg you use. On my old Matrix, the very first three shots I got were all 279. After that I got 280, 278, 280, 279... The reg is what did it. Before I had my sidewinder on, I was getting 270-290. Same thing happened with my current Cocker. After I put my Sidewinder on that, Im getting 291, 292, 291, 290, 292, 291, etc... The reg plays the biggest role, along with your paint to barrel match and quality.

I'm not flaming you in any way. I used to think the same as you, but if you sit down and actually think about it, it all makes sense. Plus, it's all been proven as well.

This has really gotten very interesting and I really wish that I had the time to get into straightening out some of the missinformation getting spread here. Simply stated, there is in fact a huge difference between the operation of closed bolt and open bolt firing. Mainly in that when a closed bolt gun actually fires, everything has stopped moving and the ball is gone before the action starts to move again. Thus giving the air a solid wall behind it to push off of when propelling the ball. This is certainly not the case with traditional open bolt firing guns since the same blast of air that fires the ball is used to open the action. On the other hand, some of the electronic guns that utilize a ram instead of a spring to drive the hammer, can come close to the same interior ballistics potential as a closed bolt firing gun. A great deal has to do with the actual tuning of the gun (efficiency) as well as it's weight and type of action. A well tuned gun can be very accurate, efficient and consistent. Regardless of its method of operation.

That is all I have time for for now but I will have time to fight the flames whe I return to the US after Nov. 7. Currently in Thailand.

Originally posted by AGD Nice discussion here guys. Yes lets say that reciprocating weight does have an effect on recoil and gun movement. Then by that thinking a heavy gun would be at an advantage because it's greater mass would move less. Do you see any accuracy difference between light an heavy markers?

AGD

ps someone measure the weight of a cocker hammer and rod and a Superbolt.

the warpig test that was done, is not something you can base facts off, they used stingrays, thats all, have you people seen the barrel on the sting ray? thats enough to take that experiment out of even questioning

Doesn't matter if the barrel were crap. If open bolt were indeed less accurate then closed bolt, it would show. Just like if you had a better barrel, but the spread wouldn't be so severe.

People have converted cockers into open bolt guns and have found no accuracy difference at all. In some cases, people have even experienced better consistency when their cocker was operating with open bolt.

y es it does matter that the barrel was crap, its unprdictble, theres to many variables to add in with the stingray test at warpig, i only see open bolt people accepting that as a test thta prooves it, even though that test was crap

Originally posted by Blazestorm
2.) The Matrix is neither closed or open bolt... not sure where I read that but it has its own bolt system.

That's just marketing gobeldy gook.

Open Bolt/Closed Bolt refers to the bolt position when the gun is at rest, not at the moment of firing.

Sitting between shots, the bolt on the Matrix is open. Thus it is an "Open Bolt," paintgun.

Because there is a common belief that closed bolt guns have some sort of inherrent advantage, Air Power, manufacturers of the Vector (same designer as the Rainmaker later) said that the Open bolt Vector was a "simulated closed bolt paintgun" because it closed the bolt before firing. That's just "marketing speak" - all paintguns with a bolt close the bolt before firing, whether they are open bolt or not. Similarly, people have applied the same term to the Matrix as a way of trying to hold onto the "closed bolt superiority" idea in the face of an accurate open bolt paintgun.

Originally posted by AGD Nice discussion here guys. Yes lets say that reciprocating weight does have an effect on recoil and gun movement. Then by that thinking a heavy gun would be at an advantage because it's greater mass would move less. Do you see any accuracy difference between light an heavy markers?

AGD

ps someone measure the weight of a cocker hammer and rod and a Superbolt.

Let us not forget Tom, that unless we're talking about a single "sniper shot" in a realistic paintball situation, people are taking multiple shots, so in the case of the 'cocker the total reciprocating mass would involve the bolt, pump arm, cylinder piston and cocking block as well.

That in mind, we're talking about inertia here, not just rest mass. Inertial force is a function of both the mass of the object and it's velocity. A faster moving, lighter bolt could impart just as much instability to the paintgun in the shooter's hands as a slower moving, heavier bolt.

Similarly, the mass of the non-moving parts at velocity of 0 (ideally held perfectly still) would counteract the inertia of the moving parts, an inertial dampener if you will.

The "ideal" steady shooting platform would have a heavy receiver, with the internal moving mass as light as possible, and moving as slow as possible to achieve the needed rate of fire. Of course the heavier you make the paintgun, the harder it is for the shooter to hold steady, due to strength issues.

Originally posted by Apocolypse somebody came out with a new electro kit for a cocker, which lets the marker operate in both open and closed bolt. it will be interesting to see how many people buy this upgrade just to see if closed bolt really is better.

If you are referring to the Firestorm kit for the Autococker, a technical writer reviewing it told me that the "closed bolt" mode is really open bolt, it just fires a little slower with a delay after the bolt has shut. At rest, the bolt is still open.

Originally posted by AGD There is another comparison to make with the barrel jump scenario. Real handguns kick like a mule and jump several inches, by the same thinking they should not be able to hit ANYTHING! So why ARE real handguns accurate? Good Deep Blue question, answer that and you will know the answer to paintball gun kick vs accuracy.

AGD

Tom, I defy you to take an "accurate" handgun, which has a lot of kick and barrel jump, empty the clip into a target as fast as we shoot paintguns, and shoot as tight a grouping as the same style shooting with an "accurate" handgun which has little kick and barrel jump. Say, a Desert Eagle .50 vs. a nice target .22.

The "recoil" has much more to do with throwing off the second, third and fourth shots than the first.

Originally posted by Treghc Desert Deagels are gas powered and have very little kick. Unless, of course, you are implying that the .22 is the gun with more kick.

Don't know what a deagle is.

But, a 50 cal Desert Eagle sure does pack a punch. Haven't shot one myself (don't really want to as I don't see the point), but to check the sights on one I saw involved bracing the gun against a post to hold it steady. Makes VERY large holes in the target as well.

Nor do you want to be in the vicinity without headphones/ear protection.

Originally posted by deded It seems that this would make a closed bolt design more accurate then an open bolt design, except for at high rates of fire. I.E. The ball is pushed into the chamber and deformed, but has time to reshapen before the blast of air pushes it out of the barrel... where as the open bolt hits the ball, deforms it, and then instantaneously shoots it out the barrel, possibly not allowing the ball to re-round as quickly as the closed bolt would.

But the nastiest thing the Ball experiences is the blast of air accelerating it to 300fps in 6 milliseconds. As has been said else where, the forces on the ball once air is applied are perfectly distributed in the rear and transfered to the ball face by the paint. The ball remains round and is infact forced round by gas pressure.

The WARPIG test proved conclusively that neither system is better. COLD HARD FACT. Same gun, same barrel, same everything except bolt operation.

Now of course we have to battle the my barrel is better than your barrel myths.

well, slarty, I've seen one or two Desert Eagles shot and had someone explain to me how they operate and why they weren't experiencing much kick at all. Maybe it's modified or something. Hell if I know

does no one pay attention to waht I say? People have converted their Autocockers to open bolt markers. Everyone that ahs done it has reported that there is absolutely no noticeable difference in accuracy. Some of them even said the consistency was better when in open bolt. Is this not yet another example of how closed bolt is not more accurate than open or am I high again?

One, on a cocker, running the Racegun setup, turning it to Sniper Mode. The Bolt won't re-cock till the you release the trigger. SO- with this setup you can easily feel where the recoil is located if you pull- then release the trigger a bit later. By separating the actions you will see that ball being launched from the barrel causes the most recoil.

Two, I have built a marker that has a bolt that weights in at 4/10ths of an ounce. Total mass is by far the lowest in the industry. Yet there is still a noticable amount of recoil. Not from the bolt. From the ball being launched.

As for the rest, recoil affects are due to total valve action, energy used per shot, mass of the gun, and deflection angle between the barrel and the hand holding the gun. The mass of the actuating parts is small compared to the 200-300 in*lbs of energy discharged in the barrel of the gun.

Josh

"If you build it they will run" - pbjosh
MM006610 bought new in '94. One owner.http://itspaintball.com For Pneu Ideas

Originally posted by Treghc might want to change your example there, bill. Desert Deagels are gas powered and have very little kick. Unless, of course, you are implying that the .22 is the gun with more kick.

The two times I've seen someone fire one, they bucked like a bronco.

The action of a Desert Eagle is of course not the point of the comparison.

I'll change the subjects to something I have fired, for a better comparison.

I can get better rapid fire groupings with my wife's brother's Remington 10-22 than with a friend's (he posts here occasionally, not sure if he wants to be pointed out for owning it) Barrett "Light 50" Model 82A1.

The Barret has sweet recoil dampening, but still it jumps the bipod 3-4 inches off the ground when shot. Even though I could shoot more accurately on a single shot than with the .22 (probably more for reasons of the sights and shooting style than anything else) the recoil after the firs shot means that I'd need to either wait until I'm settled back on target, or I'd shoot a wild grouping. If I'd cranked the Barret as fast as I do the .22, I'd muzzle climb and be lobbing shots over the horizon.

That's the issue of recoil, even if it's effect is after the ball has left the barrel, it's going to have an effect on the following shots.

By "glossed" and "buffed" I assume you mean honed and polished. You are incorrect in this statement, the barrel was honed and polished.

its like 4 inches long,

That is also incorrect, the barrel is 11" long.

I'm not sure where you got the above data about the barrel used in that test. I can't find it in the article about that test, can you please point it out to me?

and leads to unpredictable standards, you need at least reliable barrel, that would take some of the variables away,

Which components of the barrel were variable? As far as I was able to observe, it's interior finish, length, and inner diameter remained constant through the duration of the test.

I will repeat my question from earlier, what are the criteria you place for a "good" barrel? Please, not something vague, specific criteria.

also there was no reg=un predicatable consistancy
co2=unprediactable consistancy

I agree a reg would have helped consistency. You would also note, that at the time of that test regs were not commonly used in paintguns.

While the consistancy may not have been easily predicted, it was recorded, and comparable in both the control, and experimental firings. That's why the chronograph was used, and why the order of firings were swapped up to take into account changes in the pressure and temperature of the CO2 tank.

But the nastiest thing the Ball experiences is the blast of air accelerating it to 300fps in 6 milliseconds.

That is correct. Acceleration is in fact a rough experience for a paintball.

As has been said else where, the forces on the ball once air is applied are perfectly distributed in the rear and transfered to the ball face by the paint.

Yes, the air pressure is equal at all points on the rear of the ball but that only relates to the pressure.

The ball remains round and is infact forced round by gas pressure.

Not entirely true as it does not take into account the distortion of the ball as it is compressed from front to rear by the g-forces of acceleration. This causes it to tighten against the side wall of the launch tube and create friction at the sides which adds to the distortion into a cylindrical shape for at least part of its travel down the tube.

The WARPIG test proved conclusively that neither system is better.

No, that is not what it proved at all. That test only proved to me that the gun was not tuned properly to maximize the potential of true closed bolt operation. If the gun was not optimized for best results in one mode, it isn't hard to see why it would show similar results in another mode.

The only "FACT" shown is that THAT gun on that day did not show a benifit to closed bolt operation. On the other hand, if the same bolt/hammer arrangement was used for both tests (closed and open bolt firing) the results would have to be the same. True closed bolt operation requires that the chambering cycle be completely seperate from the firing cycle. Bolt and hammer operating independantly. Open-bolt firing puts chambering of the round and firing it in the same move.

Now of course we have to battle the my barrel is better than your barrel myths. :

A barrel can only be "better" if it is different than the one it is being compared to and the best barrel for a "closed-bolt" firing gun may not be the best barrel for the same gun operating in "open-bolt" mode.

viking v/s excal

The best way to fix this would be to have Larry Alexander
and crew from AKA tune a viking and an excalibur to
optimal operational condition, then test those two markers
with the same inline reg, tank, barrel, feeder, and
batch of paint.

You have two almost identical markers and this would be
a very nice test. I have not been able to get anyone from
aka to say the excal is better
than the viking or vice versa.

That interests me. I have the following observations:

Mag, with a heavier barrel shoots a tighter group.

Cocker (AKA Merlin, well tuned)
shoots as straight as i can hold it.

Bushmaster, shoots like my cocker, is faster than my mag. It has had everything
from sonic put on it, and the new circuit board and
eye from icd. I then tuned it.

The sad thing is, all of the markers hit well, group well,
and are good 'guns. I don't know why I have all of them.

If you have a marker, tbe best upgrade is to buy paint
and practice with your marker till you can hit a pod across
the field in less than 3 shots
snapping out of a bunker.

My conclusion has been that the cockers I owned were very
fun to tinker with and were easier to shoot more accurately
than my mag. I believe part of this had to do with the
movement and impulses on the marker upon firing.

My mag is a tank and cannot be
stopped (so it seems).

My bushy is a great gun, but it took a lot of money to make
it that way. I would buy an impulse w/ vision if I had
to start over again.

If I could only have one paintball marker
from now on. It would be a hard choice between an
AKA bodied cocker w/ eclipse hinge, and the emag.